Furthermore, these data are unique in another respect:
They constitute an open and `citizen science' [1]} alternative to the most used source of information on pandemic behavior: Mobility data.
As we detail below, mobility data as a source of information may be problematic from both a methodological and policy perspective.
Mobility data provides a proxy for close contacts between people and has been heavily utilized by researchers and public health institutions [2]}, [3]}, [4]}.
Mobility data quantifies the population's movement patterns and is unobtrusively obtained in a number of ways, for example, via people's smart phones and provided to researchers and governments via private companies such as Google [5]}.
This reliance, however, can and has, raised concerns.
First, in many cases, it implies that pandemic management and research relies on the willingness of private companies to share information during a critical crisis.
Second, citizens themselves may be concerned about real or perceived privacy issues related to the sharing of data with authorities [6]}, [7]}.
Given the importance of public trust for successful pandemic management [8]}, such concerns – if widespread – can complicate pandemic control.
Third, data from companies such as Google, Facebook and local phone companies may not be representative of the population of interest:
The entire population of the country.
Rather than being invited on the basis of traditional sampling methods, people opt-in to the services of different companies and, hence, the data from any single company is likely a biased sample.
Fourth, the movements of people in society as captured by mobility data is only a proxy of the quantity of interest: Actual close encounters between individuals that drive the pandemic.
